The birth rate in Spain's Catalonia region spiked after Barcelona football club lifted six trophies in 2009, medical researchers have proven.

The 2008–2009 season was a year to remember for Barcelona football club. It claimed six trophies including the Champions League trophy, the La Liga title and The King's Cup.

In May 2009, a last-minute Andrés Iniesta goal against Chelsea FC saw Barcelona make it into the UEFA Champions League final.

Nine months later, Spanish media broadcast the results of an informal poll of five hospitals, suggesting the region's birth rate had spiked by a whopping 45 percent. The so-called 'Iniesta generation' was born.

Now a group of researchers headed up by Jesus Montesinos at the Xarxa Assistencial University of Manresa have scoured through five years' worth of data at two birth centres in Catalonia to try and establish whether that Iniesta effect is real.

After looking at data of 11,000 births they found a 'significant' 16 percent increase in the birth rare in February 2010 — or nine months after Barcelona's Champions League victories, a new study in the British Medical Journal shows.

The birth rate was also 11 percent higher in March than in other years.

But the researchers are wary about drawing any quick conclusions, and argue the idea of an Iniesta generation is a misnomer. They highlight a drop in the birth rate from mid-2010 and say Spain's economic crisis may have led to fewer planned births.

"Our results may have several different interpretations," the authors said in a statement.

"One is that human emotions on a large scale can profoundly affect demographic swings in populations, that national or regional events can reduce the weight of reason and increase the weight of passion."

The researchers said validation of results could help develop contribute to a better understanding of human behaviour, "improve healthcare planning, and even aid government policy makers in stimulating or reducing birth rates".

But they said the best way to test the data would be to see "if Iniesta were willing to replicate his intervention".

They joked however that the study costs "could be prohibitive" and that the reference group — Chelsea — might not be too happy about the idea.

Spain's fertility rate in 2011 was 1.35 in 2011. This was almost the same as the 2005 rate of 1.34 but there was a slight rise to 1.46 in 2008, figures from the World Bank show.